Air relief valve for heating systems



Jan. 18, 1949- F. c. RISSELT AIR RELIEF VALVE FOR HEATING SYSTEMS Filed Oct. 27, 1944 INVENTOR. FRANK 6. 518862 7' Patented Jan. 18, 1949 UNITED STATES PAT ENT OFFICE 2,459,241 AIR RELIEF VALVE FOR HEATING SYSTEMS Frank C. Risselt, Cincinnati, Ohio, assignor to Josephine M. Risselt, Cincinnati, Ohio Application October 27,

3 Claims.

My invention relates to improvements in air relief valves of the thermostatic bellows type such for example, as is shown in Patent No. 1,825,459 of which I was joint inventor, and to improvements therein.

adjustable, but which when once adjusted, will be entirely automatic in operation.

It is also an object of my invention to provide nate condensed water.

It is an object to provide a valve having a symaking it responsive to temperature conditions therefore making it thermostatic.

The foregoing objects and other objects to shown a preferred embodiment.

Referring to the drawing, I have shown in the figure a sectional view of the assembly.

The combination consists in the base I having an internally threaded opening 2, and an externally threaded extension or coupling 3 for at- A cylindrical shell 4 threaded as at 5, engages 1944, Serial No. 560,571

the internal threads 2 of the base. A cap 6 having threads 7 engage the threads 8 of the shell 4.

The cap 6 has an internally threaded bore 9 which is engaged by the threads of an adjustable screw l0 having a notch H at its exposed end permitting movement of the screw l0 Within the threaded bore 9 of the cap, and making fine degrees of adjustment and the venting of a predetermined amount of air possible Without taking the valve apart. The elements so far described compose the valve chamber.

The valve seat I2 is formed in the screw at the lower end of a passage l3 through which the air within the radiator escapes to the atmosphere. This seat is formed as a permanent part of the 3 into the radiator or connecting pipe through which the condensed water drains back to the boiler.

It will be observed that the syphon tube M has its discharge in the extension 3 and its neck extending up substantially throughout the height of the float. This provides complete drainage at a time when the float begins to rise. float is carried upwardly by the elevation of the water level it carries the thermostatic expansible bellows l6 upwardly so that the rod l1 carrying the valve l 8 bears against the seat l2 thereby sealing the passage l Ordinarily, however, when the valve is not filled with water,

any air within the m-osphere.

To simplify the assembly of the valve and to avoid the necessity of expansive machining operation, I have shown the combination as composed of separate elements. It is within the range of mechanical equivalents to combine some of the separate elements into integral elements as long as the functions of the now separate elements are not impaired.

The operation of the relief valve will be obvious. If the valve fills up with water the float seals the air outlet passage and the syphon tube drains the water from the valve back into the supply pipe from which it flows back to the boiler if the heating system is a single pipe system.

The heat of steam within the valve, when the valve is filled with steam, also expands the bellows and seals the air bleed passage. However, when there is air in the valve the steam does not heat the bellows sufliciently to cause the valve to seat against the valve seat and air escapes to the at-.

mosphere through the passage [3 The rubber cap I9 is so formed that it compresses against a slit 20 therein thereby keeping it closed and resistant to drawing in air durin conditions of vacuum within the valve. However, the slit 2B is not sealed against opening up when air under pressure is forced out through the passage l3. The use of the rubber tip, while effective in controlling the operation of the valve, is not a feature of my invention except in the particular combination shown, as such a top is shown in the Patent No. 1,825,459 to which I have heretofore referred.

The preferred arrangement shown in the drawing is only a preferred embodiment for purposes of illustration. Changes in size and shape of the elements of the combination will readily occur to those skilled in the art. In the claims which follow it should be understood. that a steam radiator is a steam heating system but that my valve is useful on other typesof steam heating systems.

Having thus described by invention, what I claim as new and desire to secure by Letters Patent is:

1. An air relief valve for a steam heating system comprising a valve chamber having an intake at its base and an air outlet passage, and

housed within the'valve chamber, a float in the form of an open bottomed hollow member, a syphon tube and a thermostatically expansiblebellows, said expansible bellows operatively connected with a valve for closing said air outlet passage, and being in valve chamber as to be elevatable by contact with 'said float, said syphon tube having a into the intake and a neck extending up through- V such position within the discharge system havi haust port a float in the member, a s the height of ng a valve t its top and an inlet at its base, a form of an open bottomed hollow yphon tube extending up throughout chamber with an air exthe float when said float is in its lowermost position and having its intake close to the bottom and its discharge in the inlet, and a thermostatically affected expansible bellows located in the valve chamber above the float and having an operative connection with a valve for closing said air exhaust port.

3. In an air relief valve for a steam heating system having a valve chamber with an air exhaust port at its top and an inlet at its base, a

float in the form of an open bottomed hollow member, a syphon tube extending up throughout the height of lowermost position and havingits intake. close to the bottom and its discharge in the inlet, and

ing the seat of said valve.

FRANK C. RISSELT.

REFERENCES CITED lhe following references are of record in the of this patent:

UNITED STATES PATENTS Number Name Date Packard June 19, 1906 Holmberg Sept. 19, 1916 Holmberg Mar. 29, 1921 Harrison June 8, 1926 Harrison May 24, 1927 

